Why Do Some Modern Car Headlights Look Blue?

In the past, seeing blue lights on a car meant the police wanted our attention. Nowadays, some regular cars have headlights that seem to glow with a blue tint. Newer LED headlights glow brighter than older sealed-beam lamps, but a different new headlight technology is responsible for the bluish hue.

Many modern cars utilize High-Intensity Discharge (HID) technology in the construction of their headlights, resulting in this noticeable blue glow. HID lights use Xenon gas and an enclosed filament to produce their light. The temperature rating of these lights can exceed 6,000 on the Kelvin scale, indicating a cooler temperature. Cooler lights glow blue, while warmer lights like traditional sealed-beam headlamps have more of a neutral or yellow tint. 

Many drivers opt for HID headlights due to their longer life compared to other varieties of headlights. The unique blue tint also helps give some cars a more appealing look that certainly stands out from the crowd. Other drivers may find blue headlights to be quite the distraction, but are HID headlights truly more dangerous than traditional kinds of bulbs?

Blue headlights can certainly seem distracting when coming at you head-on or shining in your rearview mirror. However, you may surprised to learn that no credible link between headlight colors and accidents has been found, and as of this writing there are no restrictions on the color of factory-made headlights. 

Blue headlights can seem distracting because of the way we process different shades of light. While the lenses of our eyes  handle the absorption of most white light, blue light travels directly to the back of our eye, causing distortion and eye fatigue. Alignment can also be important in how distracting a car's headlights are to other drivers.

Regardless of what type of headlights your car has, make sure they're aimed properly to avoid hitting the mirrors of other cars. Be mindful of your distance from other drivers as well; this can cut down on the intensity of any glare your headlights might be causing. If another driver's lights shining in your mirror are bothering you, simply flip the tab at the bottom of the mirror to put it into night mode and reduce the glare.